export default {
  namespaced: true,
  
  state:()=>({
    // 购物车的数组，用来存储购物车中每个商品的信息对象
    // 每个商品的信息对象，都包含如下 6 个属性：
    // { goods_id, goods_name, goods_price, goods_count, goods_small_logo, goods_state }
    cart: JSON.parse(uni.getStorageSync('cart') || '[]')
  }),
  
  mutations: {
    addToCart(state, goods){
      // 调用数组find方法，看是否已经有商品了,有就找出来，没有就为unndefind
     const findResult = state.cart.find(x=>x.goods_id===goods.goods_id)
     console.log(findResult)
     
     if(!findResult) {
      state.cart.push(goods)
     }else{
      findResult.goods_count++
     }
     
     this.commit('m_cart/saveToStorage')
    },
    saveToStorage(state){
      uni.setStorageSync('cart',JSON.stringify(state.cart))
    },
    // 更新购物车中商品的勾选状态
    updateGoodsState(state,goods){
      const findResult = state.cart.find(x=>x.goods_id === goods.goods_id)
      if(findResult){
        findResult.goods_state = goods.goods_state
        this.commit('m_cart/saveToStorage')
      }
    },
    // 更新数据数量
    updateGoodsCount(state,goods){
      const findResult = state.cart.find(x => x.goods_id===goods.goods_id)
      if(findResult){
        findResult.goods_count=goods.goods_count
        this.commit('m_cart/saveToStorage')
      }
    },
      // 根据Id删除对应的商品
    removeGoodsById(state,goods_id){
      state.cart = state.cart.filter(x => x.goods_id !==goods_id)
      this.commit('m_cart/saveToStorage')
    },
    // 所有商品的勾选状态
    updateAllGoodsState(state,newState) {
      state.cart.forEach(x => x.goods_state = newState)
      this.commit('m_cart/saveToStorage')
    }
  },
  
  getters: {
    // 购物车中所有商品总数量
    total(state){
      
     return state.cart.reduce((total, item) =>total+=item.goods_count,0)
    },
    // 购物车中已勾选的商品的总数量
    checkedCount(state){
      return state.cart.filter(x => x.goods_state).reduce((total,item)=>{
        return total+=item.goods_count
      },0)
    },
    // 已勾选的商品的总价格
    checkedGoodsAmount(state){
      return state.cart.filter(x=>x.goods_state).reduce((total,item)=> total += item.goods_count * item.goods_price,0).toFixed(2)
    }
  }
}